Sealed pivot joints are known in which the interface between the pin and the bearing is protected against the ingress of abrasive material, or the loss of lubricant, by one or more sleeves the axial extremities of each being sealed to the pin and bearing respectively, either directly or by way of intermediate sealing members. In applications where the angular displacement of the pin relative to the bearing is limited the interface between the sleeve and the member to which it is sealed may be made as a stationary seal to reduce wear.
In known sealed pivot joints utilising such stationary seals the angular displacement of the ends of the sleeve that results when the pin and bearing oscillate relative to one another is accomodated by providing the sleeve with folds or corrugations that are free to flex and distort. However, when such sleeves are used to seal pivot joints that are used in abrasive environments it has been found that the outer surfaces of the sleeves wear preferentially in the vicinity of the corrugations. This limits the useful life of the sleeve resulting in the need more frequent maintenance of the pivot joints.
It is an object of the invention to provide a sealed pivot joint which is less susceptible to such preferential wear.